Basin 8 - Winooski River Watershed Water Quality and Aquatic Habitat Assessment Report April 28, 2008 Vermont Agency of Natural Resources Department of Environmental Conservation Water Quality Division Table of Contents Organization of the Winooski River Assessment Report ..................................................... 1 General Description ............................................................................................................ 2 Upper Winooski River watershed ........................................................................................ 5 General Description ......................................................................................................... 5 Uses and Values ............................................................................................................. 5 Significant Natural Communities...................................................................................... 8 Specific Rivers and Streams............................................................................................ 8 River and Stream Assessment Summary Upper Winooski River .................................. 12 Stevens Branch Watershed .............................................................................................. 14 General Description ....................................................................................................... 14 Uses and Values ........................................................................................................... 14 Specific Rivers and Streams.......................................................................................... 15 River and Stream Assessment Summary Stevens Branch............................................ 22 North Branch Watershed .................................................................................................. 24 General Description ....................................................................................................... 24 Uses and Values ........................................................................................................... 24 Specific Rivers and Streams.......................................................................................... 25 River and Stream Assessment Summary North Branch ................................................ 26 Dog River Watershed ........................................................................................................ 27 General Description ....................................................................................................... 27 Uses and Values ........................................................................................................... 27 Specific Rivers and Streams.......................................................................................... 28 River and Stream Assessment Summary Dog River ..................................................... 29 Mad River Watershed ....................................................................................................... 30 General Description ....................................................................................................... 30 Uses and Values ........................................................................................................... 30 Specific Rivers and Streams.......................................................................................... 33 River and Stream Assessment Summary Mad River watershed ................................... 38 Little River Watershed ....................................................................................................... 40 General Description ....................................................................................................... 40 Uses and Values ........................................................................................................... 40 Specific Rivers and Streams.......................................................................................... 41 River and Stream Assessment Summary Little River watershed .................................. 44 Huntington River Watershed ............................................................................................. 46 General Description ....................................................................................................... 46 Uses and Values ........................................................................................................... 46 Specific Rivers and Streams.......................................................................................... 47 River and Stream Assessment Summary Huntington River watershed ......................... 49 Middle Winooski River Watershed .................................................................................... 50 General Description ....................................................................................................... 50 Specific Rivers and Streams.......................................................................................... 50 River and Stream Assessment Summary Middle Winooski watershed ......................... 52 Lower Winooski River Watershed ..................................................................................... 54 General Description ....................................................................................................... 54 Uses and Values ........................................................................................................... 54 i Significant Natural Communities.................................................................................... 56 Specific Rivers and Streams.......................................................................................... 58 River and Stream Assessment Summary Lower Winooski watershed .......................... 69 Lakes, Ponds, and Reservoirs in the Winooski River Watershed ..................................... 71 Lake Monitoring ............................................................................................................. 71 Lake Water Quality Issues ............................................................................................. 73 Lake Assessment Summary .......................................................................................... 75 References and Resources ............................................................................................... 78 Appendix A: ....................................................................................................................... 80 Winooski River Watershed Biological Sampling Sites 1994 – 2006 ....................... 80 Appendix B ........................................................................................................................ 89 Housing and Population Growth in the Winooski River watershed ................................... 89 Appendix C ........................................................................................................................ 91 Dams in the Winooski River Watershed ........................................................................... 91 ii Organization of the Winooski River Assessment Report The following report on the Winooski River watershed is a compilation of information and data gleaned from numerous sources. The information comes from state agencies especially the Vermont Agency of Natural Resources (ANR) Department of Environmental Conservation Water Quality Division but also from the ANR Department of Fish and Wildlife and ANR Department of Environmental Conservation’s Facilities Engineering Division, Waste Management Division, and Wastewater Management Division. There is also information from watershed organizations, lay monitoring groups, and environmental consultants. Statewide studies on special water features such as waterfalls, cascades, and gorges as well as special natural communities were reviewed for information pertaining to the Winooski River watershed. As comprehensive as this reports tries to be, needless to say, there is inevitably data and information that were not found and incorporated. The ANR DEC Water Quality Division welcomes any additional information and any suggestions or corrections to this report. 1 General Description The Winooski River has its source in the northeast corner of Washington County in the town of Cabot then courses for approximately 90 miles northwesterly and flows into Lake Champlain in the town of Colchester just north of Burlington. It has a drainage area of approximately 1,080 square miles or about 11.9 percent of Vermont. The basin occupies all of Washington County, a little less than half of Chittenden County and small parts of Lamoille and Orange Counties. For a river length of 33 miles from the mouth to Jonesville, the valley is not more than 12 miles wide, but just to the east at Bolton where the river cuts through the Green Mountains, the valley spreads out to a width of over 30 miles. The Winooski River has seven important tributaries, three of which enter from the north: the Little River joining below the village of Waterbury; the North Branch joining at the city of Montpelier; and Kingsbury Branch joining in East Montpelier. The four branches flowing from the south are the Huntington River coming in at the village of Jonesville, the Mad River joining in Middlesex; the Dog River entering just west of the city of Montpelier, and the Stevens Branch just north of Montpelier. The land use and